Tailoring Electrolyte Composition to Improve the Activity and Energy Efficiency for the Electroreduction of CO2 to CO

Atmospheric carbon dioxide (CO₂) concentrations have been on a constant rise in the past few decades. This rise in CO₂ levels has been correlated to an increase in the global temperature anomalies leading to adverse climate change effects such as rising sea levels and erratic weather patterns. As a result, developing sustainable chemical technologies that can utilize and eventually reduce the excess CO₂ emissions is one of the grand engineering challenges of the 21^st century. Electroreduction of CO₂to value-added chemicals (such as carbon monoxide (CO), methanol, formic acid, and ethylene) using renewable energy could provide an interesting solution to this problem.

In this work, we will explore the effect of electrolyte composition on the electroreduction of CO₂ to CO using two different state of the art cathode catalysts (i.e., silver nanoparticles and gold nanoparticles supported on polymer-wrapped multi-walled carbon nanotubes). Our results indicate that the use of alkaline media (high pH) improves the activity and lowers the overpotential requirements for the electroreduction of CO₂ to CO. Additionally, we will also report results regarding mixtures of deep eutectic solvents with inorganic salts and how that can be used to integrate the process of CO₂ capture with conversion.